This invention relates to pencil sharpeners and more particularly to pencil sharpeners adapted to sharpen carpenter or construction pencils having a rectilinear cross-section.
The commonly known carpenter or construction pencil is characterized as being rectangular in cross-section with a width that is almost twice that of its thickness. Such pencils are constructed of a wood covering and a graphite core or lead. The core also has a generally rectangular or oblong cross-section.
The carpenter or construction pencil is used by carpenters and construction workers and also artists and others. However, such pencils have problem with respect to sharpening. Since almost all pencil sharpeners accept only pencils having a generally round cross-section, such sharpeners cannot be effectively used with construction or carpenters pencils. With pencils having around cross-section sharpening is attained by rotary sharpeners, which revolve about a stationary pencil or with stationary blades, which cut or peel a point on a rotating pencil. None of these offer a practical possibility for sharpening carpenter pencils. As a result, the typical method of sharpening carpenters"" pencils is to use a penknife or the like to whittle a rough point or to use sand paper to abrade a point.
Pencil sharpeners for carpenters"" pencils have been provided but such sharpeners rely on rotating cutters. Such sharpeners typically are large and cumbersome and require a stationary mounting to be effective. There is a need for a pencil sharpener for carpenter pencils, which is readily available to a user operating in the field. Preferably such a sharpener not only should be readily available but also if possible, easily carried in the users pocket or on a key chain.
It is an object of the invention to provide a pencil sharpener which is small and compact and which is easily carried by the user.
Still another object of the invention is to provide a pencil sharpener, which is cheap and economical and easy to operate.
Another object of the invention is to provide a carpenters pencil sharpener wherein the opposite wide sides and the opposite narrow sides are sharpened progressively in a manually operated sharpener.
It is another object of the invention to provide a pencil sharpener for carpenters"" pencils, which is small and compact and can be easily transported in the pocket of a worker in readiness for immediate use.
The objects of the invention are obtained by a pencil sharpener in which a base member has a cover member supported on the base member for movement between a first position in which flat cutting blades supported by the cover member are out of engagement with the pencil and a second position in which the blades are moved into engagement to cut opposed surfaces of the pencil which is held in a stationary position relative to the base member. The blades are arranged to converge relative to the axis of the pencil and are slightly curved to form outwardly concave cutting edges. Resilient means maintain the cover member in its first position and yieldingly resist movement to the second or cutting position. The base member is provided with apertures to receive the carpenter""s pencil so that one of the openings guides the pencil to a cutting position in which the wide part of the pencil is in contact with a support surface on the base member and a second position in which the narrow side of the pencil is in abutting relation with the support surface. The cover member is movable repeatedly between first and second positions to shave the end of the pencil with the cutting blades so that sharpening the pencil is attained in two stages, one for the opposed wide surfaces of the pencil and the other for the narrow opposed surfaces of the pencil. Provision is made for tilting the pencil in each of its sharpening positions to support the core or lead for accurate finishing of the paint of the pencil.